Regarding a method for synthesizing a 1-(2H)-isoquinolone derivative having a substituent at position 3, several reports have already been made. For example, in 1968, Rose et al. reported a method for synthesizing a 1-(2H)-isoquinolone derivative by reacting a 3-arylisocoumarin derivative with ammonia (see Non-patent Document 1). Further, in 1982, Poindexter reported a method for synthesizing a 1-(2H)-isoquinolone derivative by reacting N,2-dimethylbenzamide with a nitrile derivative (see Non-patent Document 2).
The pharmacological activity of these isoquinolone derivatives has also been reported. Researchers of Octamer, Inc. reported an isoquinolone derivative having anti-inflammatory action (see Patent Document 1). Researchers of Guilford, Inc. reported that 3-phenyl-1-(2H)-isoquinolone had inhibitory activity against poly(ADP-ribose) polymerase, and also reported the use of 3-phenyl-1-(2H)-isoquinolone as a radiosensitizer (see Patent Document 3). Further, it is reported that 3-phenyl-1-(2H)-isoquinolone is effective for prevention or treatment of cardiovascular disease (see Patent Documents 4 and 5).
In 1989, researchers of Du Pont reported that a 3-(1-naphthyl)-1-(2H)-isoquinolone derivative had anticancer activity (see Patent Document 2). Furthermore, it is reported that a 1-(2H)-isoquinolone derivative and a prodrug thereof have anticancer activity (see Patent Documents 6 to 8). Following the above reports, Won-Jea Cho et al. reported a 3-arylisoquinolone derivative having anticancer action (see Non-patent Documents 3 to 8).
Further, Guastavino, Javier F, et al. reported an efficient method for the synthesis of an isoquinolone derivative (see Non-patent Document 9).